Phalcon 3.4 with MongoDB and PHP7 not work

I have tried to work between phalcon, mongodb and PHP7. However, it seem not work. So I want to ask someone has worked PHalcon 3 , Mongodb and PHP7 yet. If you have, please give me a tutorial on how to make Mongodb work with Phalcon 3 and PHP7.2 please, thank you so much